According to a tweet from XTRA 910’s Mike Jurecki, Arians “is likely to become the next coordinator of the Colts.” Later, ESPN's Adam Schefter wrote that Arians has agreed to the job and will fly to Indianapolis on Monday to "to review and sign [the] contract."

So much for retirement, eh?

Well, it sounds like that’s not exactly what happened at the end of Arians’ tenure in Pittsburgh, especially since reports have emerged that Arians’ expiring contract would not have been renewed and that team president Art Rooney II didn’t give Arians a reason why the team was letting him go.

The Ravens suffered a big loss when defensive coordinator Chuck Pagano left the team to take the Colts head coaching position, but they didn't waste any time filling the role as John Harbaugh announced on Friday that linebackers coach Dean Pees would replace Pagano as defensive coordinator. Harbaugh also announced that much-maligned offensive coordinator Cam Cameron would stay with the team and receive an extension.

As we've previously noted, defensive coaches promoted by the Ravens tend to do OK later in life: four of their five defensive coordinators (with the exception of just Greg Mattison) have gone on to head-coaching jobs.

"It’s an incredible opportunity to be a defensive coordinator for anybody in this league, but it’s especially humbling to be one for the Ravens,” Pees said Friday. “I’m not going to be the same as Chuck Pagano. You got to be who you are."

Cameron's situation is a more surprising. The Ravens ranked 12th in points scored in the NFL in 2011 and 15th in yards. They finished 10th in rushing yards in 2011 but only 19th in passing yards. That's not necessarily a bad thing, though, especially considering how run-heavy their offense was at times.

Bigger concerns involve the play-calling, which was odd at times during the season, to say the least. But Harbaugh likes what he saw apparently.

"Cam has been our offensive coordinator, will continue to be our offensive coordinator," Harbaugh said Friday. "I think our coaches did a tremendous job this year."

The truth is the Ravens were just one Lee Evans foot (on a great throw by Joe Flacco) away from the Super Bowl. If Evans taps his toe before the ball's knocked out of his hands, we're not even having this conversation yet.

Harbaugh didn't provide any specifics about the nature of Cameron's extension on Friday. And he doesn't really need to unless it's a blockbuster of some sorts: Cameron will likely remain under scrutiny in 2011. Just like Flacco.

If a Ravens fan happened to be informed that one of the team’s coordinators would be fired from Baltimore before next season, that fan probably would have begun to rejoice that offensive coordinator Cam Cameron finally would move on somewhere else.

Unfortunately for those fans who wish Cameron would pack his belongings and go, the assistant coach to leave is defensive coordinator Chuck Pagano, who was hired Wednesday to take over in Indianapolis. Even worse news for those Ravens fans: despite reports that John Harbaugh might replace Cameron, the Baltimore Sun says the opposite is true.

Apparently, Cameron has begun calling his offensive assistants to give them their instructions for the next several weeks, most likely a sign that Cameron isn’t going anywhere.

Writes columnist Mike Preston: “Neither Cameron nor Ravens head coach John Harbaugh returned phone calls Wednesday night, but the source was confident that Cameron would serve in the same capacity with the only stipulation the Ravens hire a quarterbacks coach. Cameron served in both roles last season.”

NFL film-watching guru Greg Cosell recently said that the Ravens look like an offense imported from the 1960s and that their receiving corps was the worst in the league at getting open vs. man coverage.

"They don't do a lot to help their receivers win versus man," Cosell said. "I'm not going to defend [Joe] Flacco, but I think it's very difficult to … it seemed that last week [against the Houston Texans] the route tree was a go route and a screen. … Every play, there was one receiver to the right, and one receiver to the left, often two backs or two tight ends, and that was every play, it seemed."

While the Ravens defense was the biggest reason Baltimore earned a No. 2 seed in the AFC playoffs this season, the offense was a little better than you might think. According to Football Outsiders, the Ravens were the 13th-most efficient offense in the league, and behind Ray Rice and Vonta Leach, Baltimore was the 10th-best running team.

But Cameron’s play-calling came under fire when he repeatedly overused the passing game, especially when the fourth quarter was winding down and the Ravens were leading a ballgame.

It even led Ray Rice to say this midway through the season: "I'm never going to be the guy that talks about touches, but obviously we know five carries is not going to cut it. I know five carries is not going to do us any justice, but we found ourselves so deep in the situation that we had to climb our way out. We were looking for answers. Whether it was running or passing, we have to find our way out of a situation."

Still, the passing game under Flacco suffered (19th in the NFL), and there was said to be tension between the quarterback and the offensive coordinator. Which means 2012 could be awfully interesting. And for some Ravens fans, possibly infuriating.

Have you always dreamed of becoming a head coach in the NFL? Well, then you should find work with the Ravens defense, because doing so will all but guarantee you land a head-coaching job in the NFL.

Alright, it's a bit more difficult than that, but on Wednesday, Chuck Pagano became just the latest in a long line of former Ravens assistants to land gigs running NFL teams elsewhere.

The very first year the Ravens existed, 1996, the defense featured Marvin Lewis as defensive coordinator. Lewis, of course, is on his way to becoming one of the longer-tenured head coaches in the NFL and just took the Bengals to the playoffs. Lewis would leave Baltimore in 2001, coach the Redskins defense for a year and then take over the Bengals.

Working under Lewis up until 2001? Defensive assistant Jim Schwartz, who left to take the same position with the Titans, before being promoted to defensive coordinator and then taking over as head coach of the Detroit Lions in 2009.

(Notably, Eric Mangini -- 1996 as an offensive assistant -- and Ken Whisenhunt -- 1997-98 as a tight ends coach -- went on to land coaching gigs after working with the Ravens.)

In 1999, Brian Billick took over as head coach, and things really took off. He retained Lewis as defensive coordinator, but the team also hired Jack Del Rio (linebackers), Mike Smith and Rex Ryan as defensive assistants.

The Ravens won the Super Bowl in 2000. But it didn't pay off for the assistants until a year later, when Del Rio took the Jaguars job, where he stayed until being fired in 2011. Smith followed him there as defensive coordinator and would leave for the Falcons head coaching job in 2008, where he remains today.

In 2002, Mike Nolan, who'd been hired as the wide receivers coach previously, took over for the departed Lewis. Nolan, of course, went on to become the 49ers head coach in 2005. The man who replaced him? Mike Singletary, who took over as linebackers coach for the Ravens the same year Nolan became defensive coordinator.

Ryan replaced Nolan and eventually took the gig with the Jets. Greg Mattison took over for Ryan and after leaving for the University of Michigan (he took the same position under Brady Hoke), he was replaced by, you guessed it, Pagano.

Besides the Ravens, there's two other common threads with these guys: Ray Lewis, who's captained the defense since being drafted in the first round in 1996, and Ozzie Newsome, who took over as general manager that same year.

Read into it however you want; Newsome clearly has an eye for players and personnel, and Lewis clearly makes any defense better, regardless of how old he is.

But whoever takes over for the defense next should be thankful for the would-be springboard they're getting set up on.

Pagano took over as the Ravens defensive coordinator in 2011 when Greg Mattison left to become the defensive coordinator at the University of Michigan. Pagano had previously been the Ravens secondary coach for two years after a season as the University of North Carolina's defensive coordinator under Butch Davis.

It was Davis who gave Pagano his first gig in the NFL, when he left Miami University to become the secondary coach for the Cleveland Browns in 2001.

Pagano becomes the latest in a long line of folks working on the Baltimore defense to leave for a head-coaching gig in the NFL.

He also becomes yet another defensive-minded coach to take over the Colts, coming directly after Tony Dungy and Jim Caldwell. Pagano, however, isn't from the "Tampa 2" school, and is likely to shift the defense to a 3-4 style, a la what the Ravens run.

It’s getting to be about that time. Christmas? Yes, of course. Hannukah? Naturally. Festivus? It depends on your syndicated TV viewing habits. The carousel of coaches who are fired and hired, changing the courses of several franchises for the foreseeable future? Abso-freakin-lutely.

Personally, I hate to see any coach drawing the pink slip, but as Bum Phillips once said, “There’s two kinds of coaches, them that's fired and them that's gonna be fired." Jack Del Rio knows of what Phillips speaks -- he’s already been asked to vacate the Jaguars premises. And there will be plenty more firings to come.

As colleague Will Brinson pointed out in this week’s Sorting the Sunday Pile, at least seven coaches (Steve Spagnuolo, Andy Reid, Jim Caldwell, Raheem Morris, Tony Sparano, Todd Haley and Norv Turner) are on the hot seat, and that means there’s a strong possibility a whole mess of new coaches will be needed. Like last year, when I presented my list of potential coaches*, many of the candidates are career assistants who have never had a chance at a head coaching slot. Some you’ve seen in this role before. All, though, deserve a chance --- or another chance -- to run a team of their own. And who knows, maybe they’d be the one to turn around a franchise in need of a jump-start.

*Only two from last year’s list made it this list (Cowboys defensive coordinator Rob Ryan and Bengals defensive coordinator Mike Zimmer), and with Leslie Frazier, Jim Harbaugh and John Fox in new jobs, I’ve also dropped candidates like Eagles offensive coordinator Marty Mornhinweg, Giants defensive coordinator Perry Fewell and Ravens offensive coordinator Cam Cameron from consideration.

10. Bruce Arians: I had Steelers defensive coordinator Dick LeBeau on the list last year, though I figured that’s not going to happen at this point, but why shouldn’t teams take a look at Arians, Pittsburgh’s offensive coordinator? He was the head coach at Temple in the 1980s -- his record is an unshiny 21-45 -- but the paradigm shift made by the team since he’s been offensive coordinator is impressive. The Steelers are no longer a smashmouth, pound-the-rock offense. No, with Ben Roethlisberger and a trio of talented young receivers, the Steelers have entered the 21st century with their offense. There was talk Arians was a contender for the Ole Miss job, and it sounds like these people also would be rooting for Arians to get a head coaching job.

9. Joe DeCamillis: Before you say, “Why in the hell would you hire a special teams coach to be your head coach?” remember that John Harbaugh followed a similar path -- he spent nine years as the Eagles special teams coach and didn’t spend one second as a coordinator -- and it seems to have worked out OK for the Ravens. Plus, as CBSSports.com Pete Prisco said in a recent chat, DeCamillis, the Cowboys special teams ace, is organized and passionate. And if Prisco says he’s OK, it must be true.

8. Rob Chudzinski: He hasn’t spent much time as an NFL offensive coordinator, but he’s performed his finest work this year. Sure, he has some talent on his hands (Cam Newton and Steve Smith, obviously), but the work he’s done with Newton this season has been impressive. It’s difficult to remember this now, but Newton was considered a raw specimen with only one year of major college football before the Panthers took him No. 1 in the draft. But with Chudzinski’s help, Newton oftentimes plays amazing football for a rookie. It’s doubtful anybody will take a chance on Chudzinski at this point, but he’s one to keep an eye on in the future.

7. Chuck Pagano: While the Ravens offense has been in a state of flux this season, there’s little question about the effectiveness of Baltimore’s defense, which is ranked third in the league in points allowed and yards. Pagano is only in his first season as a coordinator, taking over this season for Greg Mattison, but the Ravens have been more effective this year (they were 10th in the league in yards in 2010). Pagano might need more seasoning, but he’s a guy who could ride Baltimore’s wave, particularly if the Ravens go deep into the playoffs, into a possible new job.

6. Brian Billick: There are plenty of reasons not to hire Billick. Like he said recently, he’s not young and he’s not cheap. But if you’re not necessarily looking to hire somebody for the next three decades and you have some money to spend, why wouldn’t you take a look at Billick? Yes, he’s pompous (though very good while being interviewed, and I like him on the NFL Network), but he’s also confident in his abilities. As well he should be. In nine years in Baltimore, he went 80-64, and you might remember that he won a Super Bowl title. It would take a special owner to turn to Billick, but I think it could be a very good choice.

5. Wade Phillips: The job Phillips has done in Houston this year has convinced me that Phillips deserves another chance at a head coaching job. Obviously, things didn’t end well in Dallas -- do they ever with Jerry Jones, though? -- but did you know he has a better winning percentage (.573) than Jeff Fisher (.542) and Brian Billick (.556)? And that in his nine full seasons as a head coach, he only had one losing record? There’s no doubt that Phillips knows what he’s doing as a defensive coordinator, and we know Phillips can win as a head coach as well. He’s deserving of another chance. 4. Rob Ryan: This is what I wrote last year: “We need – I mean, we NEED – another Ryan brother as a head coach in the NFL. Aside from being the most entertaining coach out there today – publically, at least – Rex Ryan has done a wonderful job turning the Jets into Super Bowl contenders. Now, Rob Ryan, the Browns (now Cowboys) defensive coordinator, needs to get his chance. With the marked improvement in Cleveland, does Ryan deserve the shot? Probably not at this point. But how awesome would it be if somebody gave him a job?” Indeed Josh from 2010, it would be pretty awesome.

3. Russ Grimm: He was finally elected to the Pro Football Hall of Fame last year as a player. Now he deserves his own team to run. He was nearly selected to follow Bill Cowher in Pittsburgh -- and some believe he was offered the job before the Steelers rescinded the offer and gave it to Mike Tomlin -- and for now, Grimm is an assistant head coach to Ken Whisenhunt in Arizona. You’d think Grimm would get his chance eventually, but he has to wonder how much longer he’ll have to wait.

2. Jeff Fisher: If you were going to hire a former head coach and you had an infinite amount of money to woo even the most resistant of people, you might go with Bill Cowher as the first choice. But my second choice probably would be Fisher. For 17 seasons with the Oilers/Titans, he recorded a 142-120 record, and he came ever so close to a Super Bowl victory. Aside from Cowher, I’m not sure there’s another former head coach out there that would command as much instant respect as Fisher.

1. Mike Zimmer: After a one-year slip-up, when the team was ranked 24th in the NFL in points allowed, the Bengals, once again, are one of the top units in the league. This, even after losing top cornerback Johnathan Joseph to the Texans and after failing to re-sign starting linebacker Dhani Jones. Zimmer has received effective play from youngsters Carlos Dunlap and Geno Atkins, and though there are no legit stars on defense, somehow Zimmer keeps making the case why somebody (anybody?!?) should give him a job. It’s time for Zimmer to have his shot.

The greatest rivalry in today’s NFL is renewed Sunday night when Baltimore travels to Pittsburgh. Though both teams have drifted towards being pass-oriented offenses, these smashmouth defenses can still make this game the type of fistfight we’ve all come to love. Here’s a look at two of the league’s meanest, most successful defensive units.

1. Baltimore’s philosophyThe Ravens are not as geared towards Byzantine blitzes as they were during the Rex Ryan years. New coordinator Chuck Pagano is more inclined to use a four-man front in nickel and let pass-rushers Terrell Suggs and Paul Kruger use their strength/speed combination on the edges.

This isn’t to say Pagano won’t blitz; he still brings some heat with inside linebackers and slot corners. But he uses stunts and the dominance of Haloti Ngata to generate individual matchups for guys outside. This creates similar end results to what Dick LeBeau does with his zone blitzes.

2. Pittsburgh’s philosophyThe zone blitz’s basic principle is getting pressure on the quarterback without sacrificing bodies in coverage. About half the time a zone blitz is actually a zone exchange, which means four pass-rushers who are coming from untraditional spots (say three rushers on one side and just one on the other, for example).

A lot of Pittsburgh’s blitzes are determined by the offense’s receiver distribution. This is a versatile approach that requires smart, experienced defenders, particularly in the defensive backfield where the coverage is usually a matchup-zone concept. Matchup zones require defenders to pass wide receivers off to one another. The Steelers and Ravens both do this extremely well.

As for Pittsburgh’s blitzes themselves, the goal is not to get pass-rushers in clean – though that’s certainly nice when it happens – but rather, to get LaMarr Woodley and James Harrison in one-on-one matchups against running backs or tight ends. The Steelers do this by overloading their attack to one side of the formation or, sometimes, aligning both Woodley and Harrison on the same side. Doing this can compel an offense to keep its running back in to pass protect, which can be a nice way to nullify a dangerous receiving threat (like, say Ray Rice).

Of course, Woodley and Harrison are likely both out this Sunday. That’s huge, especially if Jason Worilds (an unknown but gifted second-year pro who is potentially the next great Steeler outside linebacker) remains on the shelf with a quad injury. Deepening the damage is that inside linebacker James Farrior is also out. Farrior is great at timing his blitzes in a way that jars blockers and creates one-on-one matchups for others.

3. The safetiesA lot of defensive schemes look good when there’s a future first ballot Hall of Famer at safety. Ed Reed is a ridiculously smart, ridiculously rangy free safety who takes chances that no other players could take. He’s a centerfielder who’s capable of swooping into the box. Troy Polamalu is a ridiculously smart, ridiculously explosive strong safety who also takes chances that no other players could take. Polamalu is a box defender who’s capable of flying back into centerfield.

As a quarterback you obviously have to know where these safeties are at all times. Usually this kind of knowledge can tip you off as to what the defense is running. But Reed’s and Polamalu’s range allows them to disguise and redirect their intentions after the snap. Thus, the main reason a quarterback must focus on them is simply to avoid a turnover.

Something to keep in mind: Reed and Polamalu allow their respective defenses to be great in different ways. But their defenses also allow THEM be great. Neither could freelance as much as they do if not for playing with trustworthy teammates who consistently execute their own assignments.

4. Defensive LinesOn a similar note, great defenses always control the trenches. So much of defensive schemes are built around defending the pass. But effective blitzes or coverage designs are rendered moot if the offense can ram the ball down your throat. The Steelers have a stalwart nose tackle in Casey Hampton flanked by active defensive ends who can occupy two blockers by playing with strong east and west movement.

This is critical because the congestion these players create allows the linebackers to attack the run cleanly. In case there’s any doubt about how important the ends are to Pittsburgh’s scheme, recognize that GM Kevin Colbert spent his ’09 first-round pick on Ziggy Hood and his ’11 first-round pick on Cameron Heyward.

The Ravens linebackers also attack the run cleanly thanks to a potent defensive front. Baltimore’s defensive front goes about things slightly differently, though. While Pittsburgh’s ends are more athletic and aim to create congestion via movement, Baltimore’s ends are more powerful and aim to create congestion via penetration.

The emergence of nose tackle Terrence Cody has been critical this season. Cody is a load with some burst. He struggles to hold ground against double teams, but at least he’s drawing the double teams. His doing so gives Chuck Pagano more freedom in the way he uses Haloti Ngata, the most destructive defensive lineman in football.

5. Unheralded superstarsRay Lewis and Ed Reed command a lot of headlines – and understandably so. And Ngata, deservedly, gets more recognition with each passing week. But the best player on Baltimore’s defense may just be Terrell Suggs. Because the ninth-year pro has never led the league in sacks, people assume he’s merely a good player.

But Suggs’ sack numbers don’t show that he’s the best run-defending outside ‘backer in the league, playside or backside. And they don’t show how he physically wears down an opponent over the course of a game. Suggs moves like a gazelle but, when engaged in a phone booth, has the power of a rhino.

The Steelers also have a first-class star flying under the radar: Ike Taylor. It’s mind-boggling that the 31-year-old cornerback did not draw more interest on the open market this past offseason. Taylor often defends the opposing team’s top receiver man-to-man while the rest of the defense play zone.

Last week he held Wes Welker to six catches for 39 yards, which is remarkable considering Taylor is not too accustom to lining up over the slot. The week before, he held Larry Fitzgerald to four catches for 78 yards. Taylor often shows up on TV for the wrong reasons – penalties and dropped interceptions – but he shows up on film as the key to Pittsburgh’s coverages.